WHAT do you expect when you try to open a can of baked beans with a stick of dynamite?

That was the most embarrassing aspect of the first calamity caused by the AFL's ill-conceived new interchange system at Subiaco on Saturday night. It was just so achingly predictable.

The only thing that kept more egg from officials' faces was that West Coast were 39 points in front in the final quarter when the interchange stewards wrongly penalised the Eagles after Ryan Davis, a Sydney scholarship player from North Shore, had merely stepped outside the new holding pen - not onto the playing surface - before the bookwork had been completed.

What if the difference had been three points? Or 10? Or a finals spot had been on the line? Or a premiership?

Those were the type of scenarios bemused West Coast coach John Worsfold raised after the game. But, more pertinently, they were the ones raised two weeks ago when the complicated and punitive new procedures were hastily introduced in response to the Swans' fielding 19 players in the dying minutes of the Sydney-North Melbourne draw.

As several clubs, including Sydney and Richmond, had outlined in submissions to the AFL after last week's trial, the major flaw with the new rule was that clubs must hand Post-it notes with the numbers of players coming on and off to stewards before changes are made. There has still been no convincing explanation why this information could not be recorded by statisticians, but the consequence is obvious - groups of players left jogging up and down on the spot in the holding area waiting to get on the ground when their teammates have already left (the Swans briefly had six off the ground at one stage on Saturday), and even more congestion and confusion in the interchange area, something the new rule was supposed to reduce.

Inevitably, when chaos reigns, mistakes happen. Both from players such as Davis, who crept forward a metre, and from interchange officials trying to act as both accountant and traffic cop.

The obvious imperative is for the AFL to change the paperwork procedure. But it should also reconsider the punishment for minor breaches - a virtually automatic goal with the free kick paid, at the furthest, from the centre circle and a 50-metre penalty added - given it has a greater capacity to distort the results of games than the problem it was supposed to solve.

Of course, like the flawed hands-in-the-back rule, players will adjust - or officials fearing repercussions will be lenient - and the media will move on to another cause. But, like those outdated statutes that banned dancing on the Sabbath and same-sex liaisons, as long as they remain on the books so too does the capacity to cause injustice.

As it stands, it remains possible that a player using a hand to balance himself as an opponent comes back toward him could cost his team a premiership. So could a player who creeps over the boundary before the Post-it notes have been submitted.

Do we have to wait for a major explosion before common sense prevails?